The invention relates to an apparatus for the removal of areas of material punched out from a material in sheet form by projecting, closed punching edges on the circumferential surface of at least one rotating punching cylinder by means of compressed air, which is fed into the punching cylinder and is led out from the punching cylinder through outlet openings lying within the closed punching edges.
In an apparatus of this type known from the brochure "Preston" PE 752-7/85 compressed air is introduced into an axial channel of the punching cylinder through an axially displaceable pipe, in the wall of which there are holes. The pipe is to be sealed off from the channel on both sides of these holes. This apparatus is not only structurally complicated, it also does not allow strong surges of compressed air to be fed to the outlet openings within the closed punching edges.